Spotting scopes only become of value when game is spotted(using binos) and further assessment is needed(generally speaking).
BS! Spotting scopes are used for locating game in the West. I have spent countless hours behind the lens of a spotting scope looking for mule deer, elk and sheep. Without a spotting scope, hunting in the western mountains becomes a crap shoot. Miles and miles of varied, open terrain mixed with cliffs, brush trees and mountains and valleys! A spotting scope is a MUST for this type of hunting.
But to answer the OP's original question, if you can only afford one or the other, bino's will be much more useful to you. For western hunting, 8 to 10 power are the go to magnification. Some very nice glass is available now for you target budget of $400.